With two wins needed against Montenegro and Poland to guarantee progression, the midfielder is aware of the pressure ahead of the fixtures.
Roy Hodgson's side currently tops Group H by a single point and knows only a maximum return on Friday and next Tuesday will be enough to guarantee progression to Brazil next summer. And Wilshere, who has 10 caps to his name, is aware of the scale of disappointment should England fail to secure qualification.
"Ukraine was a tough game, my biggest to date, but these next two games will be another step up in pressure, no question," Wilshere told Sky Sports News. "It has not surprised me how hard the campaign has been. International football is tough.
"I know a few of the Poland players from Arsenal, and they will not give up easily, Montenegro are the same. It is in our hands now, and we have to get ready for it."
England hosts Montenegro on Friday before Poland makes the trip to Wembley Stadium for the final qualifying game.